Geeetech

Hello, I am having an issue understanding a step in the build manual for the mini rostock. It says when I am putting the universals together on page 20

Set the universal joints (one is fixed with 2 x M3*10 inner hexagon screw and another is fixed with 2 x M3 screw). The diagonal supporting arm is fixed on universal joint (1 x M3*10 inner hexagon screw + 1 x M3 rubber-washer screw).

I am not exactly sure what to do here. My main three questions are:
What is the length of the screws referred to as "2x M3 screw"?
What is an "M3 rubber-washer screw"?
Is there anyway I can get a close up picture on the joints themselves?

Thank you in advance.